Bricks



' T. POLI'VKA. KILN FOR BAKING BRICKS, TILES, POTTERY, &c.

Ew @s NEED STATES ATENT FFICE'` THOMAS POLIVKA, OF CHICAGO, ILLINOIS, ASSIGNOR TO THE AMERICAN MOSAIC BRICK AND TILE COMPANY, OF SAME PLACE,

i KILN FORBAKING BmoKs, TILES, POTTERY, sto.

SPECIFICATION forming part of Letters Patent No. 519,344, dated May 8, 1894. Applicationfled August 2'7, 1892. Serial No. 444,269. (No model.)

.To all whom it may concern;

Be it known that I, THOMAS PoLIvKA, a sub-` cate articles, which need to be guarded with articles placed in the kiln to be burned or` great care against the damaging effectsof the smoke issuing from the furnace or.` lire box of the kiln, especially when the `fire is first started, or immediately after coaling up.

Heretofore, so far as I am aware, kilns employed for` this purpose have been so constructed that the smoke, or heavy products of combustion emitted from a fresh lire, isA

compelled to come in direct contact with the baked in its passage through the kiln to the uptake, or stack. This of course results in discoloration of the articles and other damage to them,producing an unmarketable product. i

A still further ldefect of the prior constructlon is that the tiles or articles nearest the opening between the lire box or furnace and the oven are subjected to a much higher degree of heat than the others, and this inequality in the ltemperature of the ovenis so great that it often results in the complete destruction, for all useful purposes, of the articles nearest the fire, while on the other hand,

those farthest from the re are apt to be not fully baked.

It is desirable, as is well known in the art,

to employ long, low fire boxes o r furnaces for heating these kilns. Heretofore, `these furnaces or fire boxes have been fed from the front end, thus necessitating the pitching of the fuel a great distance inward in order that a proper proportion thereof may be lodged at the back or rear end of the grate. This results not only in extra labor and difficulty for the fireman, but stirs up' the fuel and pro- 5o duces dust and more than usual smoke, which agement of the fire from, the

of course are detrimental to the articles in the oven, as before explained One of the objects of my invention, therefore, is to so improve the construction of kilns that the smoke and heavy products of' combustion may be drawn into the stack or uptake without retarding the draft, or compelling the smoke, &c., to pass through the oven.

Another object of my invention is to uniformly distribute the heat throughout the oven, whereby the articles in different parts thereof may not be subjected to unequal degrees of temperature.

. Another object of my invention is to providefor the addition of fuel at, and the manside of the fire box or furnace.

With these ends in view, my invention consists in certain features of novelty in the construction, combination and arrangement of parts, by which the said objects and certain other objects, hereinafter described, are accomplished, as fully explained with reference to the accompanying drawings, and more particularly pointed out in the claims.

In the said drawings, Figure lis a vertical, longitudinal section` of my improved kiln, taken on the line 1, 1,Fig. 2. Fig. 2 isa plan section, taken on the line 2, 2, Fig. l.

Like signs of reference indicate like parts in both figures of the drawings.`

.In carrying out my invention, I provide the kiln with an upwardly extending flue, which leads from the `iirebox or furnace, and extends a considerable distance above the floor of the oven; and from some suitable point within the oven, butbelow the summit of this upright flue, I lead a discharge flue which has communication with the uptake or stack. By this arrangement, I compel the heat to first rise in the oven, and then descend, before coming into close relation with the tiles or other articles in the kiln, and inthis` way l equalize the temperature of the oven, and

`avoid overburning orbaking of the articles.

I also provide the furnace or fire box with a i by-pass Hue-passage, which establishes comy munication between the uptake or stack and the re box or furnace, independent of the upright iiue leading into the oven, and I pro- IOO m vide the said upright flue with means whereby it may be closed, so that the smoke or other products of combustion may be drawn into the discharge fiue, and thence into the uptake, without necessarily passing through the oven, or coming in contact with the articles therein. These parts maybe of any well known or suitable construction, and composed of the material ordinarily used in this art, or of any other suitable material.

' As shown in the drawings, A is the kiln proper, provided with an oven, B, having a suitable door or port, C, for admission of the articles to be burned. Thekiln A is provided preferably with a short stack, a, and the crown of the oven B is provided with apertures, h, in order that a portion of the heat which accumulates under the crown, and which otherwise would become very intense, and result in the destruction of the crown, may escape into the stack, d.

D is the discharge flue, which preferably extends downwardly from a point at or near the center of the floor of the oven, andis connected in any suitable manner, as by means of an underground fiue, d, with the uptake or stack, E. In order that the articles to be burned may be placed directly over the entrance to the discharge fiue D, the mouth of the latter is provided with a number of grate bars, F, or any other suitable supports, that will serve to sustain the articles in the oven, and at the same time permit of the passage of the heat into the flue. In order that the capacity of the discharge Hue may not be decreased by the presence of these bars, F, across its end, such flue may be provided with a Haring mouth, D', whereby the spaces or openings between the bars F in the aggregate will amount to the entire cross section of the discharge iiue proper.

The kiln may be provided with any desired number of re boxes or furnaces for supplying the oven with heat.' As shown in the drawings, I employ three of these furnaces or re boxes, each of which is placed in commu- Y nication with the oven by means of the upright iiues, H.

These upright flues H extend from the rear portion of each fire box or furnace upward into the oven B a considerable distance above the floor thereof, and they are so arranged around and adjacent to the wall of the oven that the products of combustion as they arise from such fines, and strike the upwardly concaved crown of the oven will be deflected downward upon the articles in the kiln into the discharge flue D, and thence pass on to the uptake. An advantageous manner of arranging these iiues H when but three fire boxes or furnaces are employed, is to place one of them opposite the door C, and the other two on intermediately opposite sides of the oven, so that the products of combustion arising from the latter two will meet at the crown of the oven, and hence be deflected downward, immediately over the flue D, while the products of combustion from the other one of the iiues H will be intercepted in a greater or less degreewby this downward current, and caused to travel along therewith. By the employment of these iues H leading upward into the oven, I avoid subjecting the articles in the oven to the direct iniiuence of the heat and the flame, as the latter issues directly from the furnace or re box, and consequently the damage to the articles resulting from this cause is prevented.

I provide the by-pass passage or iiue before mentioned for permitting the smoke or other products .of combustion to pass directly into the discharge flue without passing through the oven, by forming perforations or passages I through the rear walls of the fire boxes, directly into the discharge flue D; and as a means of cutting off communication between the furnaces and the oven, I provide each of the flues H with a damper or valve J, whose outer end is accessible to the fireman or attendant, whereby he is enabled at the proper time to slide suoli dampers inward, and completely close the ues H, and compel the products of combustion to pass directly into the discharge flue D vid the flues I, whence they are drawn downward into the flue d, by virtue of the superior draft of the uptake E. Thus it will be seen that when the fires are first started, or immediately after coaling up, when the smoke is apt to be heavy, any one or all of the fines H may be closed, and the oven kept clear or free from the smoke or other products of combustion that would be apt to damage the articles therein.

Each of the fire boxes or furnaces may be, provided with a double grate, that is, with one grate arranged above the other, which should be composed of re clay. The upper grate, K, is preferably very long, as shown, while the lower one, 7c, is arranged under the forward end of the other, but need not be so long. The fire on the grate 7c will render the fuel on the grate K highly combustible,by reason of the fact that the products of combustion in greater part from the lower grate will pass through the fuel on the upper grate, and consequently generate gases therein. If desired, a number of the iiues, I, may be formed through the rear wall of the furnace below the upper grate K, thus providing fora more direct escape of the products of combustion from the grate 7c when the flue H is closed. I prefer to arrange these furnaces or lire boxes G around the base of the kiln proper, extend- ,ing outward in a substantially radial direction therefrom, so as to be enabled to provide each of them in both of its side walls with doors or ports, g, through which fuel may be pushed to any desired points throughout the length of the grate bars, thus avoiding the necessity for Vpitching the fuel from the front end of the furnace the whole length thereof, as heretofore. One of the doors g may be provided on each side, just above each of the grates, K, c, and each wall, if desired, may be provided with poker holes, g. The front wall IOO TIO

rzo

of eachfurnace or fire, box may also be provided with a long door," g, opposite' each grate, for the provision of abundant draft.

t Each of these doors may be provided with a rack and dog, g", of well known construction, for holding the door open to any desired extent.

While I have shown but three tire boxes or.

furnaces, it will of coursebe understood that my invention is not limited to this precise` number, for a less number, or as many as `can be arranged around the base of the kiln might be employed Without departing from the spirit of my invention. And it should also be understood that while I have described these fire boxes or furnaces as being radially l arranged, tlhey nevertheless might be ar ranged otherwise.

Having thus described my invention, what I claim as new therein, and desire to secure by Letters Patent, is-

1. A kiln, comprising an oven and a stack,

a lue-passage leading from the bottom of the oven to the stack, a furnace communicating with the interior of the oven and containing a plurality of grates placed one above another, and by-passages leading from the furnace at points above and intermediate of the grates and also communicating with the stack` at points above and intermediate ofthe gratos thereof and also communicating with the stack-flue` at points beneath the oven, and a damper" for cutting oif communication between the furnace and the interior of the oven, substantially as set forth.

3. A kiln, comprising an oven and a stack, a plurality of furnaces communicating with the interior of the oven, a plurality of dampers for cutting o communication between the furnaces and the oven, a plurality of gratcs placed one above another in each furnace, a flue-passage leading from the bottom of the oven to the stack, and a plurality of by-pas sages leading from each furnace at points above and intermediate of its grates and communicating with the stack flue at points below the oven, substantially as set forth..

4. In a kiln, the combination with the oven of a fire box or furnace extending outwardly communication wit-h said tire box, or furnace above and belowthe upper grate, substantially as set forth.

THOMAS POLIVKA.

Witnesses:

F. A. HOPKINS, R. C. OMOHUNDRO. 

